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    <meta charset="UTF-8">
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    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
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<script>
    var num = 10;
    var srt = '10';
/*两个等号是判断里面储存的值是否相等，
相等为true，不等为false*/
    console.log(num == srt);
    /*三个等号是判断里面储存的
    值和类型是否相等*/
    console.log(num === srt);

    var x = 3;
    var y = 3;
    var z = '3';
    alert(x == y);
    alert(x === y);
    alert(x === z);
</script>
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